Sandbox



FIG. 1 is a top left side perspective view of a sandbox showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevational view thereof; the rear elevational view being a mirror image;

FIG. 4 is a right side elevational view thereof; and,

FIG. 5 is a left side elevational view thereof.

The undisclosed bottom view forms no part of the claimed design. 

The ornamental design for a sandbox, as shown and described. 